LMV431AIMFX-NOPB Datasheet, PDF (1/27 Pages) Texas Instruments – Low-Voltage (1.24V) Adjustable Precision Shunt Regulators

LMV431, LMV431A, LMV431B
www.ti.com
SNVS041F – MAY 2004 – REVISED MAY 2005
LMV431/LMV431A/LMV431B Low-Voltage (1.24V) Adjustable Precision Shunt Regulators
Check for Samples: LMV431, LMV431A, LMV431B
FEATURES
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•2 Low Voltage Operation/Wide Adjust Range
(1.24V/30V)
• 0.5% Initial Tolerance (LMV431B)
• Temperature Compensated for Industrial
Temperature Range (39 PPM/°C for the
LMV431AI)
• Low Operation Current (55µA)
• Low Output Impedance (0.25Ω)
• Fast Turn-On Response
• Low Cost
APPLICATIONS
• Shunt Regulator
• Series Regulator
• Current Source or Sink
• Voltage Monitor
• Error Amplifier
• 3V Off-Line Switching Regulator
• Low Dropout N-Channel Series Regulator
DESCRIPTION
The LMV431, LMV431A and LMV431B are precision
1.24V shunt regulators capable of adjustment to 30V.
Negative feedback from the cathode to the adjust pin
controls the cathode voltage, much like a non-
inverting op amp configuration (Refer to Symbol and
Functional diagrams). A two resistor voltage divider
terminated at the adjust pin controls the gain of a
1.24V band-gap reference. Shorting the cathode to
the adjust pin (voltage follower) provides a cathode
voltage of a 1.24V.
The LMV431, LMV431A and LMV431B have
respective initial tolerances of 1.5%, 1% and 0.5%,
and functionally lends themselves to several
applications that require zener diode type
performance at low voltages. Applications include a
3V to 2.7V low drop-out regulator, an error amplifier
in a 3V off-line switching regulator and even as a
voltage detector. These parts are typically stable with
capacitive loads greater than 10nF and less than
50pF.
The LMV431, LMV431A and LMV431B provide
performance at a competitive price.
Connection Diagram
Figure 1. TO-92: Plastic Package
Top View
*Pin 1 is not internally connected.
*Pin 2 is internally connected to Anode pin. Pin 2 should be either
floating or connected to Anode pin.
Figure 2. SOT-23-5
Top View
ANODE
REF
CATHODE
Figure 3. SOT-23-3
Top View
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2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
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